Shape:

Each mailing piece must be rectangular in shape
 

Length:

Minimum of 5" and maximum of 11 1/2"
 

Height:

Minimum of 3 1/2" and maximum of 6 1/8"
 

Thickness:

Minimum of .007 in. if no more than 4 1/4" high and 6" long
Minimum of .009 in. if more than 4 1/4" high and 6" long
Maximum of .25 in. for all sizes
Aspect ratio from 1.3 to 2.5
 

Weight:

Upgradeable Presorted First Class - Maximum of 2.5 ounces
Upgradeable Standard Mail - Maximum of 2.5 ounces
Automation First-Class Mail - Maximum of 3 ounces
Automation Periodicals - Maximum of 3 ounces
Automation Standard Mail - Maximum of 3 ounces
Automation Enhanced Carrier Route Standard Mail - Maximum of 3 ounces
Automation First-Class Mail "heavy" letter - Maximum of 3.3103 ounces
Automation Periodicals "heavy" letter - Maximum of 3.3103 ounces
Automation Standard Mail "heavy" letter - Maximum of 3.3087 ounces
Automation Enhanced Carrier Route Standard Mail "heavy" letter - Maximum
     of 3.3062 ounces
 

• Mailing piece must be a regular shape and have adequate flexibility and rigidity so that it will bend easily when traveling through processing equipment.
• When using tabs or wafer seals to seal the open edges of a mailing piece, the tabs or seals cannot interfere with the bar code or any of the postal information.
• A mail piece that is going to run through automated processing equipment cannot be polywrapped or bagged.
• A mail piece can not have clasps, button or string closures or any other type of protrusion that may damage the processing equipment.
• Rigid items, such as pens and pencils are prohibited from running through the processing equipment. Flat odd shaped items, such as a coin can be part of the mail piece but it has to be secured to the mail piece and wrapped within the piece.

1.

Return Address - Must not extend to the right more than half the length of the piece. The bottom edge of the address must not extend down more than one third of the height of the piece.

3.

OCR Read Area - The delivery address must be within OCR read area and must be in a type that is OCR readable. The OCR read area is formed by the area 1/2" from the left and right edges of the mail piece and the area 5/8" from the bottom edge up to 2 3/4" from the bottom edge.

 
Character Standards - Address characters must be no less than 0.08 inch and no more than 0.2 inch in height and uniform in thickness, not less than 3/4 pt. and no more than 2 pts. wide. Line spacing between address lines must not be less than 2 pts. or more than the height of two full characters.
 

2.

Address Window - If the piece contains a window, the address within the window must be 1/8" from all edges of the window. The clear area must be maintained with any movement of the insert in the mailing piece. The bottom edge of the window cannot extend more than 1/8" into the bar code clear zone and must be at least 1/2" away from the bottom edge of the envelope.

4.

Bar Code Clear Zone - Area in lower right corner on address side of the mailing piece. Includes area 4 3/4" from right edge of piece and the area from the bottom edge up to 5/8" from the bottom edge.
 

 
Ancillary Service Endorsements - The endorsement statements are added to the mail piece to indicate how undeliverable mail is to be handled and to request the new address of the addressee. For more information on the ancillary services that are available, see Ancillary Services below.

5.

Bar Code in Address Block - When the bar code is within the address block the rightmost bar must be more than 1/2" from the right edge of the piece and the leftmost bar must be less than 10 1/2" from the right edge of the piece and more than 1/2" from the left edge. The top edge of the bar code must be less than 4" from the bottom edge and the bottom line of the address, including the bar code, must be at least 5/8" from the bottom edge of the piece.
  

6.

Bar Code in Address Window - If the bar code is in the address window, there must be 1/8" clear area from the left and right edges of the bar code to the left and right edges of the window. The top and bottom edges of the bar code must be at least 1/25" from the top and bottom edges of the window. The clear area within the window must be maintained with any movement of the insert in the mailing piece.

7.

Bar Code in Lower Right Corner - When the bar code is in the bar code clear zone in the lower right corner, the leftmost bar must fall in an area between 3 1/2" and 4 1/4" from the right edge. The top edge of the bar code cannot be more than 7/16" from the bottom edge and the bottom baseline of the bar code must be 3/16" (±1/16") from the bottom edge of the piece.
 

8.

Bar Code Window - If the bar code is in a window in the lower right corner, there must be 1/8" clear area from the left and right edges of the bar code to the left and right edges of the window. The top and bottom edges of the bar code must be at least 1/25" from the top and bottom edges of the window and the bottom edge of the bar code must be at least 3/16" from the bottom edge of the mailing piece. The clear area within the window must be maintained with any movement of the insert in the mailing piece. The bar code does not need to be entirely within the bar code read area but it must be within the bar code clear zone.

Shape:

Each mailing piece must be rectangular in shape.
 

Length:

1. FSM 881
2. FSM 1000 
 

Minimum of 6" and maximum of 15" (see exceptions below)
Minimum of 4" and Maximum of 15 3/4"

Height:

1. FSM 881
2. FSM 1000
 

Minimum of 6" and maximum of 12"
Minimum of 4" and maximum of 12"

Thickness:

FSM 881

Minimum of .009 in
Maximum of 3/4 in
 

FSM 1000

Minimum of 1/4 in. if at lease 4" but less than 5" long
Minimum of 0.009 in. if at least 5" long
Maximum of 1 1/4 in. if 13" or less long
Maximum of 7/8 in. if more than 13" but equal to or less 
     than 15 3/4"
 

Weight:

First Class

Periodicals

 
Standard (A)
 

Maximum of 13 ounces

FSM 881 - Maximum of 16 ounces
FSM 1000 - Maximum of 6 pounds

Less than 16 ounces

• Mailing piece must be a regular shape and have adequate flexibility and rigidity so that it will bend easily when traveling through processing equipment.
• When using tabs or wafer seals to seal the open edges of a mailing piece, the tabs or seals cannot interfere with the bar code or any of the postal information.
• Mail pieces that are going to run through automated processing equipment, that are polywrapped or bagged, must meet all polywrap requirements for the appropriate FSM equipment. Polywrapped pieces must have prior approval that the polywrap material meets all physical requirements. See the Domestic Mail Manual at www.usps.gov of complete details.
• Wrapping Instructions: Direction of wrap should be around the axis of the mail piece so the seam is running top to bottom. The seam must not interfere with the address or bar code areas. The overhang on edges of the package should be within the following guidelines.

 
FSM 881

 
Overhang at top edge should be no more than 1 1/2" when contents of package are at the bottom. Overhang on sides should be no more than 1/4" on each side. Package must not be wrapped so tightly that it causes package to bend.
 

FSM 1000

The overhang on all edges cannot exceed 3/4".
 

• The mail piece may also be sleeved or inserted in an envelope. The contents of a wrapped, sleeved or enveloped mail piece should be of uniform thickness. If there is some content that is significantly smaller than the package, it should be secured to eliminated movement during processing procedures and to prevent obscuring address and bar code areas.
• A mail piece can not have clasps, button or string closures or any other type of protrusion that may damage the processing equipment.
• If staples are used as a binding method on the mail piece, they must be parallel to the bound edge and securely inserted so they do not protrude and damage or interfere with the processing equipment.

Delivery Address - Each piece must have a complete delivery address and it must fall within the OCR Read Area. Flat mail pieces must follow the same guidelines as the Letter and Card mail pieces. See Letter and Card - OCR Processing Preparation.

Bar Code - Must be on the address side of the mail piece and be at least 1/8" from any edge. The preferred location on the FSM1000 is at least 2" from the edge that is the length dimension. There must not be more than one POSTNET bar code per piece. Non-POSTNET bar codes can appear on address side but must not be recognizable by postal reading equipment.

Address Placement - A folded mail piece must have the address area showing when the final fold is at the right and any other folded or bound edge is a the bottom. Unbound flat mail pieces must have two folds, second fold being perpendicular to the first fold.

The bar code must be in one of the following areas:
 

• It can appear above the address line that is the recipient's name.
• The bar code can be below the city, state and ZIP Code address line
• It can be above or below the keyline information.
• If there is an endorsement line it can be located above or below that line.
   

Shape:

Each mailing piece must be rectangular, square or cube in shape
 

Length:

Minimum of 6" and maximum of 34"
 

Height:

Minimum of 3" and maximum of 17"
 

Thickness:

Minimum of 1/4 in. and maximum of 17"
 

Weight:

Minimum of 8 ounces
Minimum is between 6 and 8 ounces if all sides are rectangular. Mail piece must also meet or exceed minimum dimensions.
First Class Mail - Presorted: Maximum weight is 13 ounces
Standard Mail A: Maximum weight less than 16 ounces
Standard Mail B: Maximum weight is 35 pounds
Books or printed material must not be more than 25 pounds

• The packaging container must be of sturdy material to hold up through all handling processes.
• Container size must be adequate in size for contents and leave space for cushioning material when necessary.
• All cartons must meet weight size and construction standards. See Carton Standards below.
• Do not use bags, bales, bundles or wraps for difficult loads.
• Enveloped printed material and soft goods packaged in paper or plastic bags are acceptable up to 5 pounds.
• For items needing protection during handling, use cushioning material, such as foamed plastics, corrugated inserts, loose-fill or shredded paper.
• Avoid waxed or oiled materials, foam exterior boxes and packages with unsecured items.
• Be sure closure and sealing of container is adequate. See Proper Closures below.

Parcel mail pieces must follow the same OCR guidelines as Letter and Card mail pieces. See Letter and Card - OCR Processing Preparation. For information on bar codes for machinable parcels, see Bar Code Guidelines below.

3.

Ancillary Service Endorsement - An endorsement used to give instructions as to what to do if the addressee is not at the delivery address. It can be located in one of four areas.

• Directly under the return address.
• Directly above delivery address and any non-address items in the delivery address area.
• To left of postage area, and must be to left of or below any rate marking.
• Below postage area but must be below any rate marking.

1.

Special Service Marking Area - The special service markings must be directly above delivery address and to the right of the return address. For more details on marking guidelines, see the Domestic Mail Manual at www.usps.gov.

2.

Class of Service - Class of service may be shown directly below or to the left of the postage area or it can be printed as part of the postage imprint.

4.

Bar Code Guidelines for Machinable Parcels - The bar codes must contain the delivery ZIP Code and the appropriate elements for the type of symbology being used. The symbologies that are allowed until 1-10-2004 are UCC/EAN Code 128, USS Code 128, USS Code I 2/5, and USS Code 39. As of 1-10-2004 only UCC/EAN Code 128 will be allowed.

Bar Code Location:

• Bar code must be directly next to the address and must be at least 1" from the edge of the mail piece.
• It must be located on the top surface of the mail piece as it goes through processing equipment.
• There must be 1/8" clear space at the top and bottom of the bar code. The clear area at the left and right must be at least equal to 10 times the narrowest element (bar or space) of the bar code.

 
The type size used for the endorsement must be at least an 8 point size and must be clearly read on the mail piece. There must be at least 1/4 inch clear space all around (left, right, top and bottom) the endorsement statement. See Ancillary Service Endorsements for the allowable positions of the statement on the mail piece.

The information below gives the basic standards that should be considered when choosing the proper type of cartons for your mailing contents.

• For easy and average loads up to 10 pounds, paperboard boxes may be used.
• For easy and average loads up to 20 pounds, metal-stayed paperboard boxes may
  be used.
• Use the chart below to choose the proper corrugated fiberboard box according to the standards shown.
   

 
Easy Load - Its content is of moderate density that either completely fills or is packaged in containers that completely fill the mailing container. The content does not move within the container and is not readily damaged by puncture or shock. Its content is not a hazard to other packages.

Average Load - Its content is moderately concentrated items packed directly into a mailing container or are sent to an intermediate stage of package to provide partial support to all surfaces of the container. Nesting items in partitions or separate boxes can help stabilize items to prevent shifting and damage.

Difficult Load - Its content is items that require a high degree of protection to prevent distortion, puncture or shock to the content or package. Content that does not support the mailing container, such as fragile and delicate items, and high-density small bulk items, should not be sent in paperboard boxes, bags or wraps.
 

• Difficult loads boxed and going to out of town destinations must be banded about every 8 inches in each direction around the box.
• Used boxes are acceptable if the box is good and sturdy and has all flaps intact.

• Reinforced pressure-sensitive tape.
• Reinforced paper tape which is at least 2" wide and has a basis weight of at least 60-pound.
• Adhesive such as glue, paste and thermal plastic can be used. The adhesive must be serviceable from -20°F to 160°F.
• Staples and steel stitching can be used if they are spaced less than 5" apart on easy loads and for difficult loads they should be less than 2 1/2" inches apart.